/* -*- Mode: Java; tab-width: 8; c-basic-offset: 4 -*-
 	
 	        This program is free software; you can redistribute it and/or
 	        modify it under the terms of the GNU General Public License
 	        as published by the Free Software Foundation; either version 2
 	        of the License, or (at your option) any later version.
 	
 	        This program is distributed in the hope that it will be useful,
 	        but WITHOUT ANY WARRANTY; without even the implied warranty of
 	        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 	        GNU General Public License for more details.
 	
 	        You should have received a copy of the GNU General Public License
 	        along with this program; if not, write to the Free Software
 	        Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA. */
 	
 	/* more doc todo:
 	 *  threads
 	 *  gc
 	 * 
 	 *
 	 */
 	
 	package netscape.javascript;
 	
 	import java.applet.Applet;
 	
 	/**
 	 * JSObject allows Java to manipulate objects that are
 	 * defined in JavaScript.
 	 * Values passed from Java to JavaScript are converted as
 	 * follows:<ul>
 	 * <li>JSObject is converted to the original JavaScript object
 	 * <li>Any other Java object is converted to a JavaScript wrapper,
 	 *   which can be used to access methods and fields of the java object.
 	 *   Converting this wrapper to a string will call the toString method
 	 *   on the original object, converting to a number will call the
 	 *   doubleValue method if possible and fail otherwise.  Converting
 	 *   to a boolean will try to call the booleanValue method in the
 	 *   same way.
 	 * <li>Java arrays are wrapped with a JavaScript object that understands
 	 *   array.length and array[index]
 	 * <li>A Java boolean is converted to a JavaScript boolean
 	 * <li>Java byte, char, short, int, long, float, and double are converted
 	 *   to JavaScript numbers
 	 * </ul>
 	 * Values passed from JavaScript to Java are converted as follows:<ul>
 	 * <li>objects which are wrappers around java objects are unwrapped
 	 * <li>other objects are wrapped with a JSObject
 	 * <li>strings, numbers and booleans are converted to String, Double,
 	 *   and Boolean objects respectively
 	 * </ul>
 	 * This means that all JavaScript values show up as some kind
 	 * of java.lang.Object in Java.  In order to make much use of them,
 	 * you will have to cast them to the appropriate subclass of Object,
 	 * e.g. <code>(String) window.getMember("name");</code> or
 	 * <code>(JSObject) window.getMember("document");</code>.
 	 */
 	public final class JSObject {
 	    /* the internal object data */
 	    private int                               internal;
 	    private long                              long_internal;
 	
 	    /**
 	     * initialize
 	     */
 	    private static native void initClass();
 	    static {
 	        // On MRJ, this property won't exist, because the library is preloaded.
 	        String liveConnectLibrary = System.getProperty("netscape.jsj.dll", null);
 	        if (liveConnectLibrary != null) {
 	                        System.loadLibrary(liveConnectLibrary);
 	                        initClass();
 	                }
 	    }
 	
 	    /**
 	     * it is illegal to construct a JSObject manually
 	     */
 	    private JSObject(int jsobj_addr) {
 	        internal = jsobj_addr;
 	    }
 	
 	    private JSObject(long jsobj_addr) {
 	        long_internal = jsobj_addr;
 	    }
 	
 	    /**
 	     * Retrieves a named member of a JavaScript object.
 	     * Equivalent to "this.<i>name</i>" in JavaScript.
 	     */
 	    public native Object        getMember(String name);
 	
 	    /**
 	     * Retrieves an indexed member of a JavaScript object.
 	     * Equivalent to "this[<i>index</i>]" in JavaScript.
 	     */
 	//    public Object             getMember(int index) { return getSlot(index); }
 	    public native Object        getSlot(int index);
	
	    /**
	     * Sets a named member of a JavaScript object.
 	     * Equivalent to "this.<i>name</i> = <i>value</i>" in JavaScript.
 	     */
 	    public native void          setMember(String name, Object value);
 	
 	    /**
 	     * Sets an indexed member of a JavaScript object.
 	     * Equivalent to "this[<i>index</i>] = <i>value</i>" in JavaScript.
 	     */
 	//    public void               setMember(int index, Object value) {
 	//        setSlot(index, value);
 	//    }
 	    public native void          setSlot(int index, Object value);
 	
 	    /**
 	     * Removes a named member of a JavaScript object.
 	     */
 	    public native void          removeMember(String name);
 	
 	    /**
 	     * Calls a JavaScript method.
 	     * Equivalent to "this.<i>methodName</i>(<i>args</i>[0], <i>args</i>[1], ...)" in JavaScript.
 	     */
	    public native Object        call(String methodName, Object args[]);
 	
 	    /**
 	     * Evaluates a JavaScript expression. The expression is a string
 	     * of JavaScript source code which will be evaluated in the context
 	     * given by "this".
 	     */
 	    public native Object        eval(String s);
 	
 	    /**
 	     * Converts a JSObject to a String.
 	     */
 	    public native String        toString();
 	
 	    // should use some sort of identifier rather than String
 	    // is "property" the right word?
 	  //    native String[]                         listProperties();
 	
 	
 	    /**
 	     * get a JSObject for the window containing the given applet
 	     */
 	    public static native JSObject       getWindow(Applet applet);
 	
 	    /**
 	     * Finalization decrements the reference count on the corresponding
 	     * JavaScript object.
 	     */
 	    protected native void       finalize();
 	
 	    /**
 	     * Override java.lang.Object.equals() because identity is not preserved
 	     * with instances of JSObject.
 	     */
 	    public native boolean equals(Object obj);
 	}
